<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>外部样式</title>

    <!-- 引入外部的样式 -->
    <!-- 满足软件开发原则 - 解耦合 - 将html和css分离 -->
    <link rel="stylesheet" href="../css/index.css" type="text/css">


</head>
<body>
    <div>使用外部样式</div>
</body>
</html>